Are you talking about summing localization? Ortmeyer found that the level of uncertainty in localization rises between 1-3 kHz for stereophony whereas localization of a single sound source isn't frequency dependend. The effect was strongest in a free field situation. In conclusion the level of uncertainty has to be found in stereophonic playback itself. He explains it with the differing soundfield of stereophonic and monophonic playback found in that frequency range. With lower frequencies the soundfield is nearly the same. With higher frequencies shadowing effects of the head reduces the interference.
Why don't you guys read more?
Best, Markus
markus76 said:
Markus
This is pretty typical. I often quote other articles but seldom does anyone go and read them (and I'm not refering to you here, I know that you will read the pertinent stuff before bringing up a subject). It seems easier to just ask for a review or to just discount anything that is NIH.
I have to admit that I won't always go and read a reference work - it takes a lot of time.
How true. And take into account how many time is wasted by writing a multitude of posts asking the same stuff again and again. Sitting down and reading would be only a fraction of that.
Elias said:
LOCALIZATION EXPERIMENTS IN THREE-DIMENSIONAL SOUND REPRODUCTION, Theib, B. and Hawksford, M.O.J
http://www.essex.ac.uk/dces/research/audio_lab/malcolms_publications.html
Markus,
Something wrong here, your "Yes" message appeared regarding my question about Ortmeyer and then it's gone?
- Elias
Something wrong here, your "Yes" message appeared regarding my question about Ortmeyer and then it's gone?
- Elias
Hello,
Thanks for those papers.
See Figure 1 from the linked paper. That's hardly a practical living room for stereo, loudspeakers in the middle of the room and listener by the wall. I would suppose usually it's the opposite, listener at the middle of the room and loudspeakers at the wall! That must have on effect on the results?
- Elias
ScottG said:
Thanks for those papers.
See Figure 1 from the linked paper. That's hardly a practical living room for stereo, loudspeakers in the middle of the room and listener by the wall. I would suppose usually it's the opposite, listener at the middle of the room and loudspeakers at the wall! That must have on effect on the results?
- Elias
Hello,
Would you make a short list of psychoacoustic reasons why monopole would have benefits over directional source in typical reverberant living rooms in two speaker stereo in two cases 1) in freq range 20-200Hz and 2) in freq range 200Hz-1kHz?
If you claim something important would you also provide a reference so that we can read it, because we do like to read a lot 😉
P.S. we all know that a monopole may not be ideal monopole at 1kHz anymore especially if cone is big, but in that case consider comparing a 'monopole with a little directivity' to a 'more directional speaker'.
Maybe we can all learn many things from that.
- Elias
gedlee said:
Would you make a short list of psychoacoustic reasons why monopole would have benefits over directional source in typical reverberant living rooms in two speaker stereo in two cases 1) in freq range 20-200Hz and 2) in freq range 200Hz-1kHz?
If you claim something important would you also provide a reference so that we can read it, because we do like to read a lot 😉
P.S. we all know that a monopole may not be ideal monopole at 1kHz anymore especially if cone is big, but in that case consider comparing a 'monopole with a little directivity' to a 'more directional speaker'.
Maybe we can all learn many things from that.
- Elias
markus76 said:
Maybe because we are diyers in majority and not scientists? So we like conversation, several ideas, and certainly enlightening contributions from researchers and designers that have it all well in order. Me for one I can't get the gist of all those papers, especially if they have mathematics without expert guide.
Elias said:
That's discussed in the "sister" paper.😉
LOUDSPEAKER PLACEMENT FOR OPTIMISED PHANTOM SOURCE REPRODUCTION.
Its not terribly different than what I personally use - and that's without the room being used primarily for audio. Basically you move out the loudspeakers when you want to "critically" listen and put them some place else when you don't want to. It is mildly annoying though.
😀sala, my post wasn't specifically aimed at you.
A lot of papers only use minimal mathematics. They are more statistical evaluations of listening tests.
Elias, did you read http://www.gedlee.com/downloads/Cum laude.pdf ?
Have you ever looked at detailed polar response patterns? Like this:
Did any of the dipol manufacturers ever show such data?
A lot of papers only use minimal mathematics. They are more statistical evaluations of listening tests.
Elias, did you read http://www.gedlee.com/downloads/Cum laude.pdf ?
Have you ever looked at detailed polar response patterns? Like this:
An externally hosted image should be here but it was not working when we last tested it.
Did any of the dipol manufacturers ever show such data?
salas said:
Not only that, but -
Most are poorly written (I've done a fair bit of editing on similar scholarly papers, and of course had to do my own thesis in my particular discipline).
Virtually all (in this specific area) *try* to keep variables to a minimum for some degree of control, but don't really seem to "cut it" IMO.
Most don't provide enough information and/or are so complex to achieve their testing that no one actually tests their work. (i.e. there is more to the "peer" and less to the "review" in a peer review.)
All have references to prior work that can not only be difficult to get hold of, but also has the same problems (as above).
Finally in many instances much of the work often "hangs" on information gathered in a prior paper that may not only be less "complete" than desired, but often at least partially misinterpreted.
... and all of them lead to no practically applicable results
no improvement of this stereo thing over all those years
just more and more paper 🙁
no improvement of this stereo thing over all those years
just more and more paper 🙁
Scott, you're just trying to excuse ones own laziness. If one wants to learn anything than you HAVE TO read. And if you find inconsistencies, that's where the fun starts!
Hello,
That paper also suggest placing stereo speakers in the middle of the room and the listener to sit by the wall. In addition you need to sit in the correct position of an accuracy of 12mm
I know I could not sit like a statue during one record session even 😀
- Elias
ScottG said:
That's discussed in the "sister" paper.😉
LOUDSPEAKER PLACEMENT FOR OPTIMISED PHANTOM SOURCE REPRODUCTION.
Its not terribly different than what I personally use - and that's without the room being used primarily for audio. Basically you move out the loudspeakers when you want to "critically" listen and put them some place else when you don't want to. It is mildly annoying though.
That paper also suggest placing stereo speakers in the middle of the room and the listener to sit by the wall. In addition you need to sit in the correct position of an accuracy of 12mm
I know I could not sit like a statue during one record session even 😀
- Elias
markus76 said:
I disagree, to a degree.😉
Reading such a paper doesn't really prove anything to that individual reader, UNLESS they personally test the paper in virtually the exact same manner.
There is a difference between not wanting to do something vs. not being *practically* able to do something. Most people simply aren't practically able to make such tests.
Now I'll agree that it *can* be a good starting point for personal exploration in general, but so can "lurking" or participating in a thread like this (which by necessity is also reading). Better still, so can actual experimentation (..that we find is practical). Frankly any well-rounded person needs to read AND experiment, and all too often (myself included) we tend to read more than we experiment - which can pose some serious limitations and uphold erroneous conclusions often derived from reading sources.
As far as finding inconsistencies - yeah, thats fun!
😀 But in truth inconsistencies seem to abound within this topic: I mean pick *anything* within this topic alone and you'll likely have someone offering a different viewpoint on the subject.
Still, it is enjoyable to discusses the topic, and reading such papers *can* sometimes increase that level of enjoyment.
Hello,
True, but I would rather see a collaborative force of finding the 'truth' that is still out there.
Yes, that's primarily because it seems so that some people here have a hidden agenda 😀
- Elias
ScottG said:As far as finding inconsistencies - yeah, thats fun!
True, but I would rather see a collaborative force of finding the 'truth' that is still out there.
I mean pick *anything* within this topic alone and you'll likely have someone offering a different viewpoint on the subject.
Yes, that's primarily because it seems so that some people here have a hidden agenda 😀
- Elias
Elias said:Hello,
That paper also suggest placing stereo speakers in the middle of the room and the listener to sit by the wall. In addition you need to sit in the correct position of an accuracy of 12mm
I know I could not sit like a statue during one record session even 😀
- Elias
That's about right.😀
You don't actually need to be right up against the rear wall, in fact I've found it preferable to be quite a distance away from the rear wall (..though you will likely have less low freq. "support").
The degree of accuracy (listening position) signals changes in phantom source location laterally. Almost everyone has experienced this to some degree but most don't really mind a minor degree of image shift with a minor shift in seated position. And of course it can mostly be corrected with counter balance amplitude changes (i.e. adjusted the "balance" knob). It is however a real problem with multiple listeners at the same time. It could also become more or less significant to the listener depending on the loudspeaker's horizontal dispersion character.
The most "telling" thing about that position accuracy is that amplitude changes between the channels are VERY significant when critically listening. They also noted that channels needed very "tight" amplitude matching for the best localization. I recently posed an extrapolation to this for Markus: that amplitude shifts from non-uniform reflections are more detrimental than your average level and time for reflections generally. From a visual perspective the idea is this:
Consider a military graveyard where all the grave markers are precisely aligned so that if you turn your head (left or right) that the markers all seem to be "aligned" and go off into "infinity". The result is highly "uniform" and nothing "stands out". Now place just one of those markers out of alignment and all of a sudden you are attracted to that one marker - its DIFFERENT. Because its different you have difficulty ignoring it.
Non-uniform sound dispersion and reflections seem to have a similar effect, and even modest amplitude changes in one channel's primary reflection (vs. the other channel's) can alter your perception of the direct sound from both channels. It also doesn't seem to be strictly related to the first reflection, but rather all reflections (though to a lesser degree). At least that's what I've found, and its pretty easy to experiment with this using some good computers speakers (that "image" well generally) in a very small room like a small bathroom or closet.
Elias said:
Me too. (..or rather what is reasonably factual for a large sample of more critical listener's.)
Unfortunately, I think we are sometimes held-back by what is "known".
ScottG said:
That's discussed in the "sister" paper.😉
LOUDSPEAKER PLACEMENT FOR OPTIMISED PHANTOM SOURCE REPRODUCTION.
Its not terribly different than what I personally use - and that's without the room being used primarily for audio. Basically you move out the loudspeakers when you want to "critically" listen and put them some place else when you don't want to. It is mildly annoying though.
Lucky me – a setup very close to what I have found to work fine by myself – tough I doubt that dipols have been in the scope of Theiss / Gerhard / Malcolm .
🙂
Thanks for pointing to that one, ScottG
One of the benefits of dipoles when toed in is that you naturally attenuate the very first reflection (delayed phantom sources) in between of the two speakers (inverted phase as well compared to monopoles – whatever that may be good for.)
http://www.diyaudio.com/forums/showthread.php?postid=1265937#post1265937
I dropped my VVLOB concept and moved the speakers towards the middle of the room instead (and the ones develop since haven't much in common with this early concept either).
Elias said:Hello,
That paper also suggest placing stereo speakers in the middle of the room and the listener to sit by the wall. In addition you need to sit in the correct position of an accuracy of 12mm
I know I could not sit like a statue during one record session even 😀
- Elias
You should train some more in meditation then !
😀
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